An existing solution of a temperature compensation oscillator system consists of a crystal oscillator module, a temperature sensor module, a temperature compensation processing module, and an oscillator controlling module, where the crystal oscillator module consists of an oscillator module and a quartz crystal (crystal).
In the temperature sensor module close to the quartz crystal, a negative temperature coefficient thermistor senses a change in temperature and converts the temperature into a voltage signal, which is then converted into a numerical signal in the temperature sensor module. A temperature signal in a digital form is input into the temperature compensation processing module; the temperature compensation processing module converts, according to a temperature-frequency curve of the crystal oscillator module, the temperature signal into a control signal, which is input into the oscillator controlling module together with an automatic frequency control signal required by a communications system, thereby controlling an oscillation frequency of the crystal oscillator. The crystal oscillator module, temperature sensor module, temperature compensation processing module, and oscillator controlling module form an integral digital-controlled crystal oscillator (DCXO).
When the existing digital-controlled crystal oscillator works normally, accuracy of a temperature measurement value of the temperature sensor as well as correctness of the temperature-frequency curve in the temperature compensation processing module need to be ensured, so that the temperature compensation processing module can output a correct temperature compensation value. However, in large-scale applications, temperature sensors are discrete, and temperature-frequency curves of crystal oscillators are also discrete, which require calibration. Such calibration in a wide temperature range greatly affects the time and production cost in mass production.